Free standing ladders find use for gaining access to the roofs of buildings, for painting the sides of structures, as well as providing a portable means of access to a variety of elevated locations. Each year a number of individuals are injured in falls from a ladder. Many times the fall is caused by the ladder failing to remain stationary as the person climbs toward the top thereof Often, the user has failed to make certain that the lower end of the ladder is prevented from shifting or sliding away from the object against which the ladder is placed.
It is common practice to provide some sort of stabilization for the lower end of a ladder in order to prevent falls and other mishaps. Some examples of innovative devices for securing the lower end of an upright, inclined ladder are shown in the following patents.
Larson et al., in U.S. Pat. No. 4,038,047, shows a ladder pivot foot with ground spikes. Larger wedges that clip to the foot of a ladder are disclosed by Marish in U.S. Pat. No. 4,576,250, and by Jones et al. in U.S. Pat. No. 4,669,255. Fitzpatrick, in U.S. Pat. No. 5,499,691, describes an emergency breaking system using large spikes that attach to the rungs of a ladder, while in U.S. Pat. No. 5,6669,462 Jennings discloses a ladder leveling apparatus with multiple spikes to hold the ladder against slippage.
These innovative devices concentrate upon anchoring the inclined ladder bottom end to the surface directly at the base of the ladder, or a point in the surface opposite the object against which the ladder is placed. Many times there are situations where these devices cannot function as intended, such as where the base of the ladder rests on an impervious surface, such as concrete, blacktop or paving stone. Thus, there is an unmet need for a ladder anchor device that can maintain the base of an inclined ladder in a stable position on these and other surfaces.